Not trying to squeez you out of the loop but in my opinion, a good editor has no need for a sound designer to come behind him. Sweetening is by far done quickest with the project open right in front of him.
Grinner – I have been both a video and audio editor and I have to say I disagree with this comment. A good editor can do a good job with mixing, sure, but a sound designer will still do it better, if not faster.